1. Field of the Invention
The present invention relates to an evaluation device for providing a transceiver system with performance information thereof, more particularly to an evaluation device for providing a transceiver system, which models a channel thereof using Nakagami distribution, with transceiving performance information thereof.
2. Description of the Related Art
Referring to FIG. 1, a conventional transceiver system 900 under a transmit antenna selection/maximal-ratio combining (TAS/MRC) scheme includes a transmitter (TX) and a receiver (RX). The transmitter (TX) includes a modulator 91, a diversity unit 92 electrically connected to the modulator 91, and a plurality of transmit antennas 93 electrically connected to the diversity unit 92. The receiver (RX) includes a plurality of receive antennas 94, a synthesis unit 95 electrically connected to the receive antennas 94, and a demodulator 96 electrically connected to the synthesis unit 95.
The conventional transceiver system 900 is operable, in advance, to estimate the channels between the transmitter (TX) and the receiver (RX), so that the diversity unit 92 of the transmitter (TX) is operable to select one of the transmit antennas 93, which results in a channel that has relatively better performance, for transmitting a signal generated by the modulator 91. Then, when the receive antennas 94 of the receiver (RX) receive signals from the selected one of the transmit antennas 93, the synthesis unit 95 of the receiver (RX) is operable to weight and synthesize the signals received by the receive antennas 94. Accordingly, performance of the conventional transceiver system 900 is optimized, that is to say, the conventional transceiver system 900 has, for example, a relatively greater diversity gain or a relatively greater average signal-to-noise ratio (SNR).
However, the conventional transceiver system 900 under the TAS/MRC scheme merely has the optimized performance for a single receiver (Rx). When further including additional receivers (Rx), the conventional transceiver system 900 may not be able to optimize transmission performance between the transmitter (TX) and some of the receivers (RX), and thus, the overall performance thereof may be decreased.
Accordingly, a transmit generalized selection/maximal-ratio combining (TGS/MRC) scheme is provided as a solution for the above-mentioned drawback of the conventional transceiver system 900 under the TAS/MRC scheme. In particular, a conventional transceiver system under the TGS/MRC scheme does not have to select one of transmit antennas, which may result in a channel that has relatively better performance, for transmitting signals, and can be operable to transmit signals with a different one of the transmit antennas according to a different situation so as to ensure the overall performance thereof and transmission quality for various receivers.
In “Performance of Selection MIMO Systems with Generalized Selection Criterion over Nakagami-m Fading Channels,” IEICE Trans. Commun., E89-B(12), pages 3467-3470, 2006, S. Choi and Y. C. Ko proposed a method for evaluating performance of the conventional transceiver system under the TGS/MRC scheme by using Nakagami channel model (see Nakagami distribution shown in FIG. 2) to simulate the channels of the conventional transceiver system under the TGS/MRC scheme. In this method, an average output SNR and a bit error rate are computed for evaluating performance of the conventional transceiver system under the TGS/MRC scheme. However, the computational load of the average output SNR and the bit error rate is considerably large, that is to say, a number m×LR of summation operations are executed for obtaining the average output SNR and the bit error rate, where m is a fading parameter of the Nakagami distribution and LR is a number of the receiver antennas. Further, computation of an outage probability of the conventional transceiver system is not provided in this method.